NASA approves PolSIR mission for better understanding of Earth's atmosphere
What's the story
NASA has greenlit a new mission that will aid in understanding the dynamic nature of Earth's atmosphere.
Called the PolSIR (Polarized Submillimeter Ice-cloud Radiometer), the mission will survey ice clouds to determine how and why they change throughout the day.
These observations will aid in improving climate forecasts. Let us take a look at how the mission will work.
Context
Why does this story matter?
Ice clouds occur often and are known to have a profound impact on climate.
Up until now, we did not have accurate measurements to fully understand the effect of such bodies on climate, according to Ralf Bennartz from Vanderbilt University, US, who is the principal investigator of the mission.
However, that will now change with the PolSIR.
Ice clouds
Ice clouds form at altitudes of 5.5km in temperate regions
Ice clouds, which are also known as cirrus clouds, are made up of ice crystals.
These clouds start to form at altitudes of 5.5km in temperate regions and at 6.5km in tropical regions, making them the highest clouds in the troposphere.
Cirrus clouds have an impact on the Earth's radiative balance and thereby play an important role in global climate.
Formation
How do ice clouds form?
Ice clouds start as tiny particles high in the atmosphere, explained NASA.
By absorbing moisture, the ice crystals grow and become heavier, which causes them to fall to lower altitudes. Eventually, what happens is that the particles get so heavy that they fall and melt to form raindrops.
Sometimes, the ice crystals may also just stay in the air.
Official words
What role do ice clouds play?
Cirrus clouds both "alleviate and exacerbate" the effects of climate change, per NASA.
Thick cirrus clouds, with large ice crystals, aid in regulating Earth's temperature by reflecting incoming solar radiation back into space.
On the other hand, thin cirrus clouds, composed of smaller ice crystals, neither reflect solar radiation nor allow thermal radiation emitted by the Earth to escape our atmosphere.
Mission
PolSIR will specifically study ice clouds in high altitudes
The PolSIR will monitor ice clouds that form at high altitudes in tropical and subtropical regions.
The mission comprises two identical CubeSats, each satellite measuring just over 12 inches in height.
The satellites will be able to measure the thickness and amount of ice clouds in the atmosphere, said Bennartz. Over time, it will observe the clouds' daily cycle of ice content.
Information
The mission will provide crucial information for climate modeling
The observations made by PolSIR will provide a better understanding of how ice clouds impact the climate. The mission will help climate models in making more accurate global and regional projections and ultimately aid in adaptation and mitigation efforts, explained Bennartz.
Official words
'Radiometers will improve our understanding of ice clouds'
"Understanding how ice clouds respond to a changing climate and then, in turn, contribute to further changes remains one of the great challenges to predicting what the atmosphere will do in the future," said Karen St.Germain, from NASA's Earth Sciences Division.
Radiometers, which measure radiant energy emitted by clouds, will "improve understanding of how ice clouds change and respond throughout the day," she added.
Information
When will the PolSIR mission launch?
In order to bring down costs, the PolSIR is most likely to take off along with another mission or commercial satellite. However, as of now, there is no launch window mentioned by NASA.